Question

Answer this question no.06

Answer 1

Given:-

•Initial velocity(u)=20m/s

•Final velocity(v)=0 (As it finally comes to rest)

•Distance covered(s)=50m

•Mass of the stone(m)=1kg

To find:-

•Force of friction between the stone and the ice(F)

Solution:-

By using the 3rd equation of motion,we get-----

=>v²-u²=2as

=>0-(20)²=2×a×50

=>-400=100a

=>a= -400/100

=>a= -4m/s²

Now,by Newton's 2nd law of motion,we get----

=>F=ma

=>F=1×(-4)

=>F= -4N

Thus,the required force is -4N and the negative sign here,signifies that the force is retarding.